Reversing gear for internal combustion engines



May 7' .H. WALT! I 2,080,882

REVERSING GEAR FOR INTERNAL COMBUSTION ENGINES Filed July 18, 1934 ToENGINE 40 FULL s ar-:0 ASTERN I STOP 5 BKFULL s zeo AHEAD 4 I/STARTINGAHEAD TARTING ASTERN ASTERN STARTING ASTERN INVENTOR:

H15 T QR EY$ Patented May 18, 1937 UNITED STATES PATENT OFFICE REVERSINGGEAR FOR INTERNAL COMBUSTION ENGINES Application July 18, 1934, SerialNo. 735,816

In Switzerland July 22,1933

4 Claims.

-This invention relates to oil-burning engines,

and especially those for marine duty. It is,

more particularly, concerned with the control andreversing geartherefor, and its general ob- 5 ject is to provide an improved controlfor starting, running, and reversing such engines.

-'A particular object is to provide a control gear in which prematureor'undesired re-commencing of combustions, invariably the cause of the'lag or delay in changing direction from ahead to astern, will beprecluded, and by simple means.

In accordance with the present invention the fuel injection pump, afterbeing rendered inoperative preparatory to reversing the direction ofrotation of the engine is maintained inoperative until the direction ofrotation of the engine actually has taken place. Itis then restored toits operative condition by cooperating toothedmembers, which act asgears, being brought-into operative engagement to shift one of-saidmembers to a position in which it actuates suitable means to restore thefuel-injection pump to operative condition.

The objects and advantages of the invention will become more manifestfrom the following description of an illustrative example, taken inconjunction with the accompanying drawing, but the invention is limitedin its embodiments only by the scope of the sub-joined-claims.

In the drawing, Fi'g. 1 is a typical schematic lay-out, quitediagrammatic, showing the parts of the controlmechanism in thefull-speed ahead position;

Fig. '2 is a similar view showing significant parts at the beginning ofthe starting astern position, and v I Fig; 3 is a similar view of a moreadvanced stage-ofthat position.

The mechanism shown in Fig. cylinder I of 2. Diesel engine includes,among other things, a starting valve 2, a compressed air-pipe 3, andmanifold 3', connected thereto, a cam shaft 4 (which changes itsdirection of rotation when the direction of the engine changes), areversing lever 5, and a fuel pump 6. The'starting valve 2 isreciprocated by the engine I in the usual way by conventional means, notshown. "The fuelpump 6 includes a piston I, a fuel-intake valve 8, afuel-discharge valve 9, and-a plunger I for reciprocating under andagainst the intake valve I 8.

Anarm II is provided and mounted for displacement back and forth in thehorizontal direction. The member II bears a lug I2 and a 1 applied to alongitudinal slot I3. The cam shaft 4 bears a collar I4 fixed thereonadjacent the arm II, and the collar has two oppositely located lugs I5thereon, they and the collar being so arranged that they move in thesame vertical plane as 5 the lug I2. A small cylinder I1 is provided andsuitably mounted below the lever II. The cylinder contains a piston I6under the influence of the starting-air, as the cylinder I1 is connectedto the pipe 3 by a smaller pipe I8. The 10 piston I6 bears on its upperend a roller I9 which therefore maintains II constantly in contact withI4 in all positions,

The lever II, is connected by slot I3 and pin 24, to a link 20, mountedat its lower end on the fixed pivot 2i. The link carries a roller '22 atits upper end, and is movable laterally between two fixed'stops 23. Alever is mounted adjacent the roller 22, and bears a cam-face 26. Thedistal end is pivoted to the starting lever, 5. 20 A plunger 21 isvertically mounted in a fixed member or guide 28 adjacent lever 25, andis supported on it by a roller '29. The plunger terminates at its upperend in a horizontal arm as. The part 30' engages the plunger III of the25 fuel pump.

A check valve 32 is provided behind the starting valve 2 and is loadedby a spring 33. A piston 34 is mounted on a cylinder 35 and rigidly 7connected to valve 32. A valve 36 is mounted 30 in a casing 36 andconnected on its upper, or inlet, side by a pipe 31 to the starting-airpipe 3. On its discharge side it is connected to. the top of cylinder 35by a pipe 38, An opening 39 exhausts the casing 38' to atmosphere. Thevalve 3-5 38 is actuated by a rod 40, which rod is actuated by theextension 4| of member '30. The rod 4|] isadapted to be moved up into aconstriction 22 when it has pushed the valve 36 upwardly,

and then the rod 40 closes off the discharge to 40 atmosphere.

When the lever .5 is brought from the full speed aheadf position shownin Fig. 1, into the starting astern position shown in Fig. 2, in orderto reverse the drive, and the direction of the ship, thestarting valve 2is by this movement, in the conventional manner, (not illustrated)opened and set in operation.' The valve 8 at the same time is lifted bymeans of the cam 26 moving over the roller 22. This results incompletely shutting off all fuel from the engine and admittingstarting-air into the cylinder. By these means, the engine is firstbraked to a momeritary standstill, and thereafter it is forced to rotatein the reverse direction.

' mosphere, the valve 32 acts as a check-valve, and

Until reverse rotation starts, bolt II will be held fast, in its extremeleft-hand position by the frictional thrust of the ring M which is stillturning in the direction of the arrow up to the moment of change ofdirection of rotation. At this moment of change, the ball will be movedby friction toward the right, and finally, when one of the detents l5bears on the detent l2, it will be forcibly displaced to the rightbringing the lever 20 and the roller 22 into the right-hand positionshown in Fig. 3. In this way the member l4 effects the movement of thelever 25, and plunger 21, and pin I!) by causing them to fall downwardlyunder their own weight, whereby the suction valve 8 is released and thefuel-pump again starts to work. Lever 20 and cam 26 constitute alatching mechanism for holding lever 25, plunger 21 and valve-actuatingpin H] in their upper positions as shown in Fig. 2.

When the engine is reversed by means of lever 5, the valve 8 and thevalve 36 are pushed up simultaneously. Thereupon, piston 34 opens valve32. Hence, the engine-piston, not shown, (the engine still running byinertia in the former direction of rotation), on up-stroke forces backthe starting-air through the valve 32 and valve 2, and can, withoutproducing excessive compression in the starting-air-pipe 3, act as acompressor. The braking action thus produced stops the engine promptly.

Since the engine cylinder can, by the present invention, begin toreceive fuel again only from the very moment the direction of rotationof the crankshaft actually begins to change, any premature setting inagain of combustion, or firing, is rendered quite impossible, and thisis accomplished by the relatively simple means above described. Also,since at the very moment the direction of rotation changes, the valve 36is closed, and cylinder 35 is thereby connected again to atany back-fireof the combustion intothe starting-air pipe will be made impossible.

Various refinements and modifications in the above construction areconsidered as being within the scope of this invention; for example, thelever H, instead of being constantly pressed against the collar l4, maybe pressed temporarily or intermittently, and each time only at the verybeginning of the reversing operation.

I claim:

1. A reversing gear for internal combustion engines comprising a devicefor controlling the fuel supply to said engine, a member for actuatingsaid device manually movable to cut off said fuel supply, a latch forholding said member in such position, and means for tripping said latchcomprising a circular member adapted to be rotated by the engine, alaterally movable member connected to said latch and held in frictionalengagement with said circular member during the operation of reversingthe engine, and lugs on said circular member and said laterally movablemember adapted to be brought into coaction by the frictional engagementof said circular member and said laterally movable member upon thereversal of rotation of said engine to move said member laterally andtrip said latch.

2. A reversing gear for internal combustion engines comprising a devicefor controlling the fuel supply to said engine, a member for actuatingsaid device manually movable to cut off said fuel supply, a latch forholding said member in such position, and means for tripping said latchcomprising a circular member adapted to be rotated by the engine, alaterally-movable member connected to said latch, lugs on said circularmember and said laterally-movable member adapted to be brought intocoaction by the frictional engagement of said circular member and saidlaterally-movable member upon the reversal of rotation of said engine tomove said member laterally and trip said latch, and means for bringingsaid laterally-movable member into frictional engagement with saidcircular member prior to the operation of reversing the engine.

3. A reversing gear for internal combustion engines comprising a devicefor controlling the fuel supply to the engine, a member for actuatingsaid device manually movable to cut off said fuel supply, a cam on saidmember, a latch for holding said member in such position, means fortripping said latch comprising a circular member adapted to be rotatedby the engine, a laterallymovable member connected to said latch, lugson said circular member and said laterally-movable member adapted to bebrought into coaction by frictional engagement of said circular memberand said laterally-movable member upon the re-' versal of rotation ofsaid engine to move said member laterally and trip said latch, and meansfor causing said laterally-movable member to bear frictionally againstsaid circular member prior to the operation of reversing the engine,said manually-movable member being interposed between said latch and apart of the device for controlling the fuel supply to the engine, thecam of said manually-movable member, upon operation of said member, toreverse the engine, cooperating with a part of said latch to cause themanually-movable member to operate said control device to cut off thesupply of fuel to the engine.

4. A reversing gear for internal combustion engines comprising a devicefor controlling the fuel supply to the engine, a member for actuatingsaid device manually movable to cut off said fuel supply, a cam on saidmember, a latch for holding said member in such position, said latchincluding a lever having a roller carried thereby which normally engagessaid manually-movable member to assist in guiding the same in itsmovements, means for tripping said latch comprising a circular memberadapted to be rotated by the engine, a laterally-movable memberconnected to said latch, lugs on said circular member and saidlaterally-movable member adapted to be brought into coaction by thefrictional engagement of said circular member and said laterally-movablemember upon the reversal of rotation of the engine to move said memberlaterally and trip said latch, and means for causing saidlaterallymovable member to bear frictionallyagainst said circular memberprior to the operation of reversing the engine, said manually-movablemember being interposed between said roller and a part of the device forcontrolling the fuelsupply to the engine, said roller by engagement withsaid cam during movement of the manually-movable member to reverse theengine raising said memher and causing it to actuate thefuel-controlling device to out 01f the supply of fuel to the engine,said latch, when tripped, permitting the manually-movable member to falland the fuel-controlling device to be actuated in the reverse directionto restore fuel delivery to the engine.

' HEINRICH WALTI.

